Have kidney stones alot but first time they hurt. I'm peeing blood, than my low left side hurt, what's best med? How can I find out y I get them?

Renal stones. Go to ER /urgent care now for pain medication may need antibiotics as well as may have infection . Once the pain has resolved follow up with urologist , they can test stones and see what is it made up of and direct you if needed to dietary changes that may lessen the incidence of renal colic. A nephrologist can work with the urologist to optimize renal function.